Washington is digesting news the United States will, for the first time, deploy Special Forces in Syria to support local fighters battling Islamic State militants. The move is a sharp departure from troop withdrawals in other conflict zones approved by President Barack Obama.

Friday's announcement prompted debate on the presidential campaign trail, but no wild cheers from Democratic or Republican candidates vying to succeed Obama in 2017.

'Either they win or we do'

Republican Senator Marco Rubio said Islamic State extremists must be confronted.

“Either they win or we do. They are not going to stop in Syria. They are not going to stop in Iraq," said Rubio. These people have to be defeated. And you defeat them by denying them operating territory.”

“This president ran on the promise of: We are getting out of the way, we are in retreat," Rubio said. "He got elected by arguing, ‘We are out of Iraq. We are soon going to be out of Afghanistan. Vote for me.’”

But Rubio said he does not favor a massive U.S. military deployment to fight the Islamic State directly. Rather, according to the senator, America must do more to rally the broader Middle East to battle Sunni radicals.

His recommendation sounds similar to that of Democratic presidential candidate Bernie Sanders, who said he fears a deployment of up to 50 troops in Syria could be just the beginning of a larger commitment.

“Fifty troops is 50 troops. But here is my nightmare: My nightmare is that the United States once again gets caught up in a quagmire, which never ends and which leads to perpetual warfare," Sanders said. "The world has got to come together.”

Clinton weighs in

Fellow-Democrat Hillary Clinton’s campaign issued a statement saying Clinton “sees merit” in a limited deployment to Syria, but opposes a larger ground war in the Middle East.

The White House stressed a train-and-assist role for Special Forces sent to Syria.

“These forces do not have a combat mission,” said White House spokesman Josh Earnest. “The president does expect that they can have an impact in intensifying our strategy for building the capacity of local forces inside Syria, to take the fight on the ground to ISIL in their own country.”